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buzzaro
07-11-2006, 07:47 PM
use Trimble equpment/software? If so ive got some questions for ya.

GunninGopher
07-11-2006, 08:47 PM
Fire away.
5700/5800/R8/TSCe/TSC2/TCU/S6...
Whata got, i've used 'em all.

GunninGopher
07-11-2006, 08:48 PM
Oh, yeah TM2e and TM3, too.
Right, can't forget about TGO

GunninGopher
07-11-2006, 09:07 PM
OK,
I've also used 4000/4700/4800/TSC1, but that's been a while.

buzzaro
07-12-2006, 03:51 AM
OK,
I've also used 4000/4700/4800/TSC1, but that's been a while.
Hehe, glad you mentioned this stuff. Were still using these relics daily.
My question is this: Using trimble equpment (4800 w/ TSC1) I performed a survey locating some flight panels we had laid down. The site was rather large and the control network we were using (that was previously established) was even larger. Couple that with the fact some some points in our network had been destroying during road improvments, the choices for base setup was less than ideal. We have recently began using two base stations to observe each flight panel to eliminate some error and provide another check to each shot (all of this in RTK). However in this case due to the great distances and terrain I was having much radio trouble so I decided to use faststatic to reduce the time. The bases were started in RTK/Infill so the heads were logging. Since I had started the survey in RTK in the rover as well, the job was calibrated. I took the equipment back to the office and downloaded the heads and DC. Now I am being told that I will have to go out and re-do the survey because the postprocessing results are coming back strange since the job was calibrated. The office is using TGO. This seems really strange to me since the DC uses all the same information to get the same results during RTK. Any light you could shed on this would be great. Thanks

GunninGopher
07-12-2006, 06:08 AM
I have today off to pack for the river so I'll see if I can help. RTK and static in the same job!! Why don't you throw in a little terrestrial work!!!
I mix terrestrial and RTK all the time, but not Static very often. I also haven't used a site calibration with static data, but I'd be suprised if that simple combination alone would cause a problem. Site calibrations simply create a projection, a transverse mercatur, I believe. As long as TGO was told to use the data collector's definition that alone shouldn't matter.
If I had to guess what the problem is I'd say that TGO is constraining to coordinates that you don't want it to. When you do a site calibration, you cannot bring in any other geodidic coordinates to hold, and your static data is probably fixing the WGS coordinate of each of your static occupations. Points can be 'enabled', 'enabled as a check' or 'disabled'. There are also 2 types of coordinates "CG" (Grid) and "CW" (WGS '84 geodedic). Expand the points in TGO and look to see if any CW points are enabled. I don't know how the survey was conducted, but to investigate this problem, I would disable the CW's and enable the CG's. You may need to keep the CW point of the original site calibration base enabled, but not any others. Also be sure to combine the common controls points so that you only have 1 instance of them.
If that doesn't work rethink how the survey progressed and look at those points in TGO. Make sure that only the original base point has the CW enabled.
A couple of things to note, which you likely already know:
You can only do 1 site calibration in each TGO and DC file. Is it possible that you moved the base and stored another 'here' position? That's a no-no.
Make sure that the proper coordinates are being used in TGO. On import it will ask if you want to use the project or DC projection definition. Use the DC one.
If you were set up and running in infill (I seldomly do) then why did you switch to static? The big reason to run an infill survey is to be able to continue surveying when the radio is a problem.
You did process the static baselines, correct? This is an add on module for TGO that you may not have.
Your static occupations were long enough, right?

buzzaro
07-12-2006, 03:31 PM
I have today off to pack for the river so I'll see if I can help. RTK and static in the same job!! Why don't you throw in a little terrestrial work!!!
Didnt have my gun with me that day :cool:
Site calibrations simply create a projection, a transverse mercatur, I believe. As long as TGO was told to use the data collector's definition that alone shouldn't m
If that doesn't work rethink how the survey progressed and look at those points in TGO. Make sure that only the original base point has the CW enabled.[/B]
A couple of things to note, which you likely already know:
You can only do 1 site calibration in each TGO and DC file. Is it possible that you moved the base and stored another 'here' position? That's a no-no.
Did not do a 2nd here position, the calibration was created a few years ago, i was just locating some fight panels.
Make sure that the proper coordinates are being used in TGO. On import it will ask if you want to use the project or DC projection definition. Use the DC one.
If you were set up and running in infill (I seldomly do) then why did you switch to static? The big reason to run an infill survey is to be able to continue surveying when the radio is a problem.
I only started the base using that survey style so that it would log data as opposed to using RTK survey style which would not, I did not actually survey using that style (plus no one I know is 100% sure how it works and has played with that style to confirm what we think :idea: )
You did process the static baselines, correct? This is an add on module for TGO that you may not have.
I am not using TGO myself, but the guys in office are and yes the baselines were processed.
Your static occupations were long enough, right?
Yes the occupations were OK
The main thing the office guy is telling me is that because the job in the DC is calibrated that the baselines are coming out incorrectly, what he said he wanted to do with an uncalibrated job was process the baselines and then scale to the same point the original calibration was scaled to/from. I think that since the calibration is done there should be no more scaling and the solution to the vectors just needs to be solved using the static data. The stuff you put in bold definately sounds like its hitting the nail on the head.

RandyH
07-12-2006, 04:28 PM
can these devises be used to locate keys? If so I am buying one for my wife. :)
RandyH

GunninGopher
07-12-2006, 05:47 PM
Hopefully it all worked out.
I usually work in SPC's without a calibration, but I don't think being in a calibration was your problem.
TGO can get irritating with what it thinks is the best position to hold. Most of us would rather work completely in grid, and TGO likes geodidic.